排序方式: 共有43条查询结果,搜索用时 15 毫秒
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Ivonne Nel Thomas C. Gauler Kira Bublitz Lazaros Lazaridis André Goergens Bernd Giebel Martin Schuler Andreas-Claudius Hoffmann 《PloS one》2016,11(4)
PurposeDue to their minimal-invasive yet potentially current character circulating tumor cells (CTC) might be useful as a “liquid biopsy” in solid tumors. However, successful application in metastatic renal cell carcinoma (mRCC) has been very limited so far. High plasticity and heterogeneity of CTC morphology challenges currently available enrichment and detection techniques with EpCAM as the usual surface marker being underrepresented in mRCC. We recently described a method that enables us to identify and characterize non-hematopoietic cells in the peripheral blood stream with varying characteristics and define CTC subgroups that distinctly associate to clinical parameters. With this pilot study we wanted to scrutinize feasibility of this approach and its potential usage in clinical studies.ResultsWe detected CTC with epithelial, mesenchymal, stem cell-like or mixed-cell characteristics at different time-points during anti-angiogenic therapy. The presence and quantity of N-cadherin-positive or CD133-positive CTC was associated with inferior PFS. There was an inverse correlation between high expression of HIF1A, VEGFA, VEGFR and FGFR and the presence of N-cadherin-positive and CD133-positive CTC.ConclusionsPatients with mRCC exhibit distinct CTC profiles that may implicate differences in therapeutic outcome. Prospective evaluation of phenotypic and genetic CTC profiling as prognostic and predictive biomarker in mRCC is warranted. 相似文献
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The interaction of a glycosylphosphatidylinositol (GPI) protein with different detergents was studied for the first time with a purified protein. Four differently hydrophobic fractions of GPI-alkaline phosphatase (GPI-AP) from calf intestine were used as model proteins. The mode of interaction was determined by investigating (i) the self-aggregation behaviour of the GPI-AP fractions, (ii) the interference of detergents with GPI-AP binding to octyl-Sepharose, and (iii) the elution of GPI-AP bound to octyl-Sepharose. It was shown that polyoxyethylene-type detergents surprisingly interact much stronger than n-octylglucoside with GPI-AP, which is in contrast to the known behaviour of GPI-proteins in natural membranes. Gel filtration chromatography of Triton X-100 at concentrations above the critical micellar concentration yields three different micelle species with apparent molecular weights of about 166, 54, and 16 kDa. GPI-AP fraction II, which is shown to bear only one anchor per dimer, does not bind to any of these micelles. We demonstrate that a complex is formed containing about 150 Triton X-100 molecules and about 4700 molecules of water per molecule of GPI-AP dimer. The experimental findings are in accordance with a simple geometrical model based on the physical data of fatty acids and the arrangement, mean size, and shape of Triton X-100 molecules. 相似文献
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Johannes D Clausen Maike Bublitz Bertrand Arnou Cédric Montigny Christine Jaxel Jesper Vuust Møller Poul Nissen Jens Peter Andersen Marc le Maire 《The EMBO journal》2013,32(24):3231-3243
The sarco(endo)plasmic reticulum Ca2+‐ATPase (SERCA) couples ATP hydrolysis to transport of Ca2+. This directed energy transfer requires cross‐talk between the two Ca2+ sites and the phosphorylation site over 50 Å distance. We have addressed the mechano‐structural basis for this intramolecular signal by analysing the structure and the functional properties of SERCA mutant E309Q. Glu309 contributes to Ca2+ coordination at site II, and a consensus has been that E309Q only binds Ca2+ at site I. The crystal structure of E309Q in the presence of Ca2+ and an ATP analogue, however, reveals two occupied Ca2+ sites of a non‐catalytic Ca2E1 state. Ca2+ is bound with micromolar affinity by both Ca2+ sites in E309Q, but without cooperativity. The Ca2+‐bound mutant does phosphorylate from ATP, but at a very low maximal rate. Phosphorylation depends on the correct positioning of the A‐domain, requiring a shift of transmembrane segment M1 into an ‘up and kinked position’. This transition is impaired in the E309Q mutant, most likely due to a lack of charge neutralization and altered hydrogen binding capacities at Ca2+ site II. 相似文献
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Clark Bublitz 《Molecular and cellular biochemistry》1991,108(2):141-144
A rapid, convenient method for the assay of glucose 6-phosphatase dependent on the removal of radioactive substrate from radioactive product by Dowex 2 fluoride is described. The enzymatic reaction is stopped by the addition of an ethanolic slurry of the resin. After the tubes are shaken, the radioactivity of glucose in the clarified supernatant layer is measured. The release of glucose is directly proportional to time and enzyme concentration. Detergents do not interfere with the method. 相似文献
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C Bublitz 《Analytical biochemistry》1978,88(1):109-113
A procedure for the assay of cyclic nucleotide phosphodiesterase is described in which labeled cyclic nucleotide is separated from labeled nucleoside by the batchwise addition of ethanolic slurries of Dowex 2 fluoride. Under the conditions described there is no detectable adsorption of nucleoside by the anion exchanger, which removes more than 95% of the tritium in boiled samples of [8-3H]cAMP or [8-3H]cGMP. Linear time courses and enzyme vs activity relationships are described for 10?3 and 10?7m cAMP and 10?4m cGMP. The method is limited by interference by neutral salts and by the enzymatic conversion of adenosine into inosine. 相似文献
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Fletcher Nichola Terschak John A. Bartels-Hardege Helga D. Bublitz Ralf Schirrmacher Paula Hardege Jorg D. 《Aquatic Ecology》2022,56(2):419-427
Aquatic Ecology - The reproduction of many brachyuran crustaceans involves the formation of mating pairs often around the time of the female moult with attraction of a sexual partner and mating... 相似文献
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